Carburetor for internal-combustion engines



Dec. 10, 1929. JENSEN 1,739,396

CARBUHETOR FOR INTERNAL COMBUSTION'ENGINES Filed May 13, 1926 3 Sheets-Sheet 1 v m as Fig. '2.

Dec. 10, 1929. JENSEN 1,739,396

CARBURETOR FOR INTERNAL COMBUSTION ENGINES Filed May 13. 1926 3 Sheets-Sheet 2 3 Fi a. 3

,ZFj//OWF L. 75 /757? Dec. 10, 1929. 1.. JEN SEN 1,739,395

CARBURETOR FOR INTERNAL COMBU$TION ENGINES 7 Filed May 5 1926 s Sheets-Sheet 3 119 45 v F1515 -f Patented Dec. 10, 1929 FFE PATENT l LETH. JENSEN, OF PARIS, FRANCE v CARBURETOR FOR IN TERNAL-COMBUSTION ENGINES Application filed May 13, 1926, Serial No. 108,896, and in France May 22, 19 25.

operation in cold Weather or in hot Weather.

In connection with carburetors for internal combustion engines suggestions have been made previously to provide between the float chamber and the induction pipe of the engine a rotatable plug serving to control the passage of the mixture of air and petrol to the engine. f

According to the present invention an open ended tube provided with a calibrated hole 0 adjacent each end thereof is removably fitted into a central passage in a jet carrier, the holes adjacent the opposite ends of the tube being of "dilferent size, while the tube is reversible so that one or other of said .holes may be brought into the operative position for'controlling the passage of petrol, one of said holes for example being adapted for use in cold weather while the other is adapted for use in hot weather.

The invention will now be described with reference to the accompanying drawings,

. wherein a Figure 1 illustrates a vertical section of the carburetor. Figures 2 and-3 are horizontal sections on the line AB of Figure 1, Figure 2 showing the parts in position for normal running and Figure 3 showing the parts in position for slow running.

Figure 4 is a side elevation of the nozzle holder.

Figure 5 is a longitudinal section of the 7 tube.

Figures lland 12 are respectively side elevation and plan views of the lid.

Figure 13 is a side elevation of the regulating float.

Figure 14 is an elevation view of a modified form of carburetor.

Figure 15 is a longitudinal section of the same carburetor taken along the line IIII in Figure 14.

Figure 16 represents a diametrical section of a valve or plug forming a detail modification shown in Figs. 14 and 15 in which is a vent for admission at low speeds.

Figure 17 is a transverse section of the carburetor taken along the line XVII'XVII of Figure 15.

The carburetor shown in Figures 1 to 13 inclusive, is provided Witha body 1 with a flange 2 for securing itto the engine. This body 1 has a main air intake pipe 3 and an outlet pipe 4 for supplying the mixture to the engine.

Between the two pipes 3 and 4 there is arranged a member 5 which will be referred to as the nozzle carrier and which is surrounded --by a controlling plug 6 (illustrated separately in Figures 7 8 and 9) Thisplug 6 is fitted on the nozzle carrier by which it is guided and it can turn without friction in a circular recess formed in thebody 1 between the pipes 3 and 4. It is of general cylindrical shape,

:hollow and provided with two main orifices 6,

6 which are adapted, according to the angle of rotation, to coincide partially or completely with the sections of the pipes 3 and 4. The plug 6 is also'provided with a small lateral orifice 6" for slow running, and in its lower face with a groove 6A which forms communication between the two main orifices 6.

The portion of the nozzle carrier 5 between the pipes 3 and 4 is of elongated section as shown in Figures 2 and 3 or it may be circular, With its central portion of reduced diameter, as shown in Figures 4 to 6, so as to divide the main stream of air entering through the pipe 3 into two streams which re-join beyond the nozzle carrier.

An auxiliary air inlet 7 is formed by a lateral passage provided in the body 1 and which may be partly or completely uncovered by means of a slider 8 adjusted and suitably guided on the outer cylindrical surface of the body 1.

The nozzle carrier is secured to the body 1 by means of a nut 9, and is extended upwardly by a cylindrical portion 5 and down wardly by a cylindrical portion 5 Along its whole length it is provided with a central passage 10 which terminates at the bottom of the part 5 in an orifice 10 provided for the passage for fuel and for a rod 26,'connected to a float24, Small lateralorifices 11 are also provided in the lower end of the part 5 and communicate with the ori: fice 10.

At acertain point of-the length of-thiscentral recess 10 there opens; a small inclined passage 12 which terminates on the lateral surface of the part 5 at the side of the pipe 1.

Into the central passage 10 isplaceda tube 13 which rests on the bottom of the passage, extends alongi'the-whole length thereof and 7 passes beyond its upper'end. This tube 13 is of smaller diameter than the recess 10 in such a manner as toidividethe passage into a central space and an annular space 1 1'. The lower end of the inclined passage 12 leads from this annular space 1.4, the-opening thereof being at about the level of fuel: int-he float chamber 20.

The tube 13 (Figure 10) is provided adjacent its ends with two small holes 3 and13 the lowermost'hole serving forthe passage of fuel from the central spaceto the annular space 14. These two holes are ofdifferent diameter and calibrated in such a manner as to serve one asthe nozzle duringsummer time and the other as the nozzle for wintertime.

As the tube 13 is simply resting in the cyl indrical recess 10it thus suffices, according to the surrounding temperature, to place the tube in the recess in such amanner as to place in the bottom of the latter the hole 13 or 13 which is toserve as a nozzle,the hole at the topbeinginoperative as a nozzle and serving solely for a small initial admission of air". as hereinafter described. The facility of removing andreplacing this tubefor the initialadjustment of the carburetor will be readily seen. By the use of two or three tubes with different size holes it will be seen that the carburetor can be adjusted to suit the prevailing atmospheric conditions. It may be mentionedthat the nozzle'tube 13 bay be removed by hand and withoutthe necessity of closing the supplyof fuel;

The lower end ofthe tube 13 bears on the truncated bottom of the cylindrical recess 10 and its upper end bears against a cap 15 which is screwed on the screw-threaded endon thepart 5 of the nozzle carrier 5. Y a

This cap'15 is provided with a hole at the center through which passes the rod- 26 of the float 24, and for the admission of air.

The plug 6 is provided with a portion forming a flange to which is secured a stud 16, connected to rod mechanism or operated in any suitable manner, by means of which the driver can turn the'plug 6 into the required angle for controlling the admission of air.

The upper part 6" of the plug is covered by a cover 17 of which the periphery 17 engages with a circular recess in the body 1. The cover 17 is secured in position by anut 18 screwed on the screw thread of the portion 5 of the nozzlecarrier. This cover isprovided with a groove through which passes the stud 16 and which limits the movements of the latter and thus of the plug 6. This construction permits-the operating mechanismto be disposed in such a manner that this may be actuated either by pulling or pushing according to the case of application.

This cover 17, of dome shape, (Figures 1-1 and 12). is slightly flexible in such amanner that when tightening the nut 18 it tends to slightly flatten and thus tightens itsperiphery 17 in the circular recess of the body 1.

In the body 1 there is provided a passage 19 adapted to form communication between the outer atmosphere'and the interior of the float chamber 20.. p

The float chamber 2 0is secured tothe. un-

derside of the body 1 by screw threadingat 20 or by another method of securing.

The fuel enters the bottom of the chamber 20through a vertical passage-21: from aviilter 22 of any suitable construction, which receives the fuelfrom a tankby thepipe 23.-

The float 24 is provided at its lower end with a valve member 25 which seats in the opening of theinlet: passage 2lpfor the fuel; To the bottom of the float2 lthere'is secured the vertical rod 26 which passes through the orifice 10 at the'bottom of the recess1O of the nozzle carrier, extends alongthe whole length of the tube 13 and'beyond the-cap 15.

The operation of the carburetor is asfollows n For starting, the chamber 20 is flooded by raising the float 24 by meansof the rod26- which projects beyond the cap 15.

The liquid then enters the chamber 20Jdriv- V the float 24 which passes into thenozzle car rierthrough the orifices 10 and 11 to the same level as in the float 24, and by passing through the hole in the lower end of the tube 13 passes to the same level in the annular space 14 around the tube 13.

From the annular space 14 the fuel, mixed wit-h a small quantity of air entering the up per part of the annular space14 is drawn through the inclined passage 12.

The admission plug 6, which is actuated by the stud 16, is set for starting in the position just beyond that shown in Figure 3 so as to cover the inclined passage 12.

In this position air from the pipe 3 and fuel from the passage 12is drawn through the small hole 6 provided in the plug 6 on the side of the engine and situated at the level of the inclined passage 12.

At slow speedtie admission of air is effected through the lateral orifice 7 of which the area of opening is adjusted by the slider 8. This slider may be actuated at will from the drivers seat or may be fixed in the position giving the best result.

lV hen accelerating the plug 6 is gradually moved to the position shown in Figure 2 so that during this movement the wall of the plug gradually closes the orifice 7 for additional air (Figure 2) and thus all the air drawn in can only enter through the pipe 3 and must pass 011 each side of the body of the nozzle carrier 5 and is mixed intimately with the rich mixture arriving through the passage 12. The complete mixing and homogeneity of the mixture are ensured by reason of the fact that the passage 12 for the rich mixture being inclined, the mixture which it supplies is projected upwardly into the inlet pipe 4 for the mixture. It will be understood that any vacuum which may be produced at high speeds in the pipe 4 is de stroyed by the air which passes from one orifice 6 of the plug to the other orifice 6 by the auxiliary passage formed between these two orifices by the groove 6A.

These different peculiarities of construction enable a carburetor to be produced of simple construction and of little expense, and of small size which can be easily applied to engines of different types.

In the modification shown in Figures 14 to 17 inclusive the jet holder 5 can be construct ed to operate as principal diffuser in case the carburetor is fitted to certain types of engines.

To this end, the central portion of the nozzle-holder has a concave circular surface on the outside and this surface is pierced with several rows of emulsion holes 27-27 communicating, at the centre of the part, with the hollow space 10.

A circular groove 28, arranged at the bottom of the central portion of the nozzle-hold er, causes the holes 27 to communicate with one another, these holes being arranged according to the lowest row.

As will be observed from Figure 16, vents 29 of suitable number and shape, are arranged through the side of the circular base of the plug 6. The function of these vents is to establish communication between the nozzle 13 and the passages 3 and 4 according to the path formed by the holes 27 groove 28.

The vents 29 are arranged in such a way that they come progressively in front of the openings 3 and 4 according as the plug 6 is turned in the direction of the closing of the principal intakes.

When running at a slow speed, or when starting up the engine to which the carburetor is added since direct communication of the openings 3 and 4 is prevented by the sides of the plug, feeding is carried out exclusively by the vent or vents 29, directed towards the tubing 4, section of the orifices of these vents being able to be adjusted on occluding more or less, those orifices with the edge of the tubing 4.

In this way, the device enables exact mixture proportions, to be obtained, according to needs. p

With respect to the circular plug openings, the position of the vents 29 in the circumference of the plug 6 is such that when accelerating, that is to say at the moment those openings are uncovered on one of the sides 'of-the interior orifices of the tubings, the

principal admission of gases begins before the orifices of the vents 29 are completely hidden behind the side opposite the tubings.

Under these conditions, it will be understood that a passage from slow to higher engine speeds takes place progressively, the sections of the intake orifices of the tubing 4 constantly increasing during acceleration.

On the other hand, admission of the rich mixture which, during slow running, only took place through the vents 29, is now operated according as the plug 6 rotates, through an increasing number of openings of the emulsion holes 2727, as fast as they are uncovered and subjected to the engines suction.

As can be seen from Figures 14 and 17, this form of carburetor is supplied with a hot-air intake tubing 31 that can be brought into connection with the secondary air intake 7. The aim of this hot-air intake is to facilitate starting of the engine when cold, and to supply hot air at all intermediary en gine speeds. VJ hen starting up, control of the hot air intake is ensured by means of a diaphragm or axis shutter 32 the position of which can be regulated by the driver. Apart from starting up, the diaphragm remains open and the hot-air intake is adjusted automatically according to the position of the plug 6 in relation to the tubing conveying hot air.

These difierent particularities and these and the different methods of construction andgrouping of means permit establishment, in all cases, of a carburetor that is simple, and not very costly to manufacture, not very bulky and capable of being adapted easily to different types of engines.

It is to be understood that this carburetor just described, as Well as the special shapes and arrangements mentioned for the different organs and as are shown in the attached drawings, only constitute examples of application of the invention to which all modifications can be added with regard to the shape, arrangement and even the number of parts and elements constituting the carburetor, Without departing from the scope of the invention by so doing.

lvhat I claim is:

A carburetor comprising a'body having a float chamber, cup-shaped submersible float in said float chamber, liquid fuel eduction means extending to a point adjacent the bottom of said float, the latter being provided with a stem extending through said liquid v. fuelleduction means to the exterior of the carburetor.

In testimony whereof I have signed my name to this specification.

LETH JENSEN. 

